Entex Space Invader Chip labeled MP1211 MSL^8114 28-pin SDIP die labeled MP1211 3 buttons: Left/Right/Fire 1 switch: Pro/Am Piezo buzzer LEDs: 44 LEDs - 7 rows by 6 columns plus 2 extra above lowest row 3-digit 7-segment LED TMS1100 pinout 1 R8 - middle digit 2 R9 - left digit 3 R10 - Piezo 4 VDD 5 K1 - Fire 6 K2 - Left 7 K4 - Right 8 K8 - Pro mode 9 INIT - N/C 10 O7 - LED matrix 11 O6 - LED segment G / LED matrix 12 O5 - LED segment F / LED matrix 13 O4 - LED segment E / LED matrix 14 O3 - LED segment D / LED matrix 15 O2 - LED segment C / LED matrix 16 O1 - LED segment B / LED matrix 17 O0 - LED segment A / LED matrix 18 OSC1 - connected to OSC2 and 56pF disc cap (to VSS) and 47K resistor (to VDD) - Pro mode adds 180K resistor (to VDD) 19 OSC2 - OSC1 20 VSS 21 R0 - LED matrix 22 R1 - LED matrix 23 R2 - LED matrix 24 R3 - LED matrix 25 R4 - LED matrix 26 R5 - LED matrix 27 R6 - LED matrix 28 R7 - right digit 7-segment LEDs O0 O1 O2 O3 O4 O5 O6 R7 right digit A B C D E F G R8 middle digit A B C D E F G R9 left digit A B C D E F G LED matrix 7 rows by 6 columns, with extra LEDs above bottom row O0 O1 O2 O3 O4 O5 R0 . . . . . . R1 . . . . . . R2 . . . . . . R3 . . . . . . R4 . . . . . . R5 . . . . . . R0 . . R6 . . . . . . Extra LED on right is R0+O7, left is R0+O6